Day: November 7, 2011

The guys from the House4Hack hackerspace in Johannesburg won the 2011 Google+ Hackathon with their Friggin’ Laser Turret. The build started off as a remote-controlled webcam that can be controlled by anyone in a Google+ hangout. On a whim, the team decided to add a laser to the build because lasers are awesome.

The inspiration for the build was to have a Google+ hangout available whenever someone is at the hackerspace. If a guest can’t grace the team with their physical presence, at least they can be there virtually. The camera is controlled by an Arduino running a bog-standard servo library implementation. The Arduino is connected to a laptop over a serial connection and is able to move left and right. To spice things up a little, the team added a 25mA laser diode to the build controlled from a digital output on the Arduino.

For winning the Jo’burg Google+ Hackathon, the guys scored themselves a Samsung Galaxy S II phone. Not a bad prize for building something cool. Check out the demo of the friggin’ laser turret after the break.

[Abdullah] got his hands on some flex sensors and attached them to a glove. These resistive sensors are put through a voltage divider and sent to a microcontroller (a PIC16F778, we believe) and corresponding MIDI notes are chosen. These MIDI notes are sent to a computer and played over a speaker.

Right now, only a single arpeggio is coded into the microcontroller. Depending on which finger is bent shifts this arpeggio up and down the keyboard. That being said, the firmware can be easily modified to recognize standard piano fingering so chords can be played. The only issue is moving the hand up and down the keyboard.

[Abdullah] is planning on making his glove completely wireless with a microcontroller and battery sewn into the glove. Here’s to hoping he’ll keep us posted.

Hackaday reader [Kieran] volunteers at an outdoor haunted house attraction called the “Disenchanted Forest”. Attendees are lead through the haunted forest by a volunteer, who helps keep everyone on the predetermined trail. The trail is usually lit by small LED fixtures that the group constructed, but the organizers wanted to make the lights more interactive this time around.

A fellow organizer gave [Kieran] a [Harry Potter] Magic Candle, which allows him to light the toy with the wave of his IR-enabled wand. He was told to “make it do something cool”, so he took a closer look at it to determine how everything worked.

Using an Arduino clone and some borrowed IR code he was able to get the wand to work with the forest’s trail lighting, but there was a lot of lag between waving the wand and triggering the light. Taking a second stab at it, [Kieran] was able to replicate the IR protocol used by the toy, speeding things up and increasing the wand’s range considerably. Now, the tour guides can light and extinguish the trail lighting with a simple flick of the wrist.

Take a look at the video below to see how things worked out for [Kieran], and be sure to swing by his site for more details if you have the urge to modify your Magic Candle.